The surfaces of wood material boards, particularly high density fiberboards, features a coloring that can change from charge to charge, and even within a charge. This effect occurs particularly clearly upon a change in the wood formula used for producing the wood material board and/or in the condition of the thermomechanic pulping. Wood material board workpieces are therefore often primed before printing. The primer should ensure an even coloring from both board to board and charge to charge, such that the subsequent printing leads to a reproducible result. The wood material board workpieces are generally primed to be white. In order to achieve this, the wood material board workpiece is primed with several applications of white pigmented synthetic resins, such as melamine resin. Before the printing, the primer is dried in order to reduce the proportion of water in the synthetic resin.
However it has been proven that, despite the primer being applied under identical printer settings, different printing results are achieved on the wood material board workpiece over time; this is undesirable.